Castro is currently in Las Vegas awaiting extradition to San Diego County to face charges for the murder of 23-year-old Antonia Herrera. Herrera was shot several times in the torso, according to Nelson. Her body was found on the side of Champagne Boulevard on Jan. 12.

Las Vegas Metropolitan Police told Sheriff’s investigators that Castro was a documented gang member in the area, though law enforcement wasn’t releasing what gang he is a member of.

Castro’s arrest for the murder stemmed from physical evidence found at the scene as well as witness statements, according to Nelson.

Herrera did have a residence in San Marcos, though often traveled back and forth to Las Vegas, to visit friends, where she had had past residences, Nelson said.

Nelson described the relationship between Herrera and Castro as “acquaintances.”

He said she was on her way back home when she was killed.

During the investigation, autopsy results had been sealed.

“Usually when we have a homicide investigation and we don’t know who the suspect is, and we have very few leads, we hold back, we seal the medical examiner’s report,” said Nelson. “Because when we go to question people, we want to make sure that what they’re telling us, they’re not getting through things that they’ve learned through open sources, like media and social media platforms.

“We want to make sure that they’re telling us what maybe a real witness would know or something the suspect would actually know.”

Tips came in from Las Vegas to people in San Diego, which ended up making their way to local investigators, Nelson said.

Sheriff’s investigators made multiple trips to Las Vegas, Nelson said. “With the help of Las Vegas Metro Police Department, we served multiple search warrants at multiple locations in this investigation. We spent countless hours in Las Vegas following up on all leads.”

On Herrera’s Facebook page, numerous postings showed an outpouring of support that justice would be served.

“Baby girl justice is coming !!!,” one post read. “My heart is heavy but I smile for this. Finally justice for you and for your family. Justice for the lives you’ve touched who’s hearts are hurting because someone took you from us. But justice is coming and for that I smile, I may cry but I smile too. You may physically be gone but nobody can take away the memories. I know you’re watching over us and for that I smile. I love you so much! RIP Baloni!”